1. Field of the Invention
The present invention relates to a method of producing an optical element obtained by laminating a functional layer on a base material and to an apparatus for producing the optical element.
2. Description of the Related Art
A liquid crystal display device (LCD) has found use in a variety of fields such as a television and medical equipment because the device has advantages such as the ease with which the thickness and weight of the device are reduced, the ability of the device to reduce power consumption, and the difficulty with which a flicker occurs. On the other hand, the device involves the emergence of, for example, a problem in that light leak or atone reversal phenomenon occurs depending on the angle at which a user views a liquid crystal display screen, so a viewing angle is narrow, and a problem in that color heterogeneity occurs in the liquid crystal display screen or contrast reduces.
In order to solve the problem, there has been proposed a liquid crystal display device provided with an optical element that controls an outgoing light emitted from a liquid crystal cell and an incident light entered into the liquid crystal cell.
For such the liquid crystal display device, there has been proposed an optical element having a film obtained by orienting and fixing a liquid crystal molecule in a specific direction as well as a film obtained by subjecting a triacetylcellulose (TAC) film to uniaxial stretching or biaxial stretching.
JP 05-142531 A proposes a viewing angle compensation film composed of a nematic liquid crystal polymer whose molecular chain is oriented in a normal direction of the film surface and which has a positive intrinsic refractive index. JP05-142531 A discloses that the viewing angle compensation film may be obtained by: forming a vertical alignment layer on the surface of a glass substrate or the like by using an alkylsilicone-based or fluoroalkylsilicone-based surface treating agent to produce a cell; sealing liquid crystal molecules into the cell; and subjecting the liquid crystal molecules to photopolymerization.
JP2002-174724 A proposes a method of producing a liquid crystal layer in which a polymerizable liquid crystal compound is homeotropically oriented, the method involving applying the liquid crystal compound to a vertical alignment layer formed on a substrate. The method involves the use of a long-chain alkyl-type dendrimer derivative as an agent for forming a vertical alignment layer. In addition, JP 2002-174724 A discloses that a film including a homeotropically oriented liquid crystal film can be obtained by means of the method, and that the film can be used for an optical film such as a retardation film.
JP 2002-174725 A proposes a method of producing a homeotropically oriented liquid crystal film involving: applying, to a substrate provided with no vertical alignment layer, a side-chain type liquid crystal polymer containing a monomer unit containing a liquid crystal fragment side chain and a monomer unit containing a non-liquid crystal fragment side chain; further homeotropically orienting the liquid crystal polymer in a liquid crystal state; and fixing the polymer while the oriented state is maintained.
JP 2003-121852 A proposes a method of producing a homeotropically oriented liquid crystal film involving: forming, on a substrate provided with no vertical alignment layer, a binder layer and an anchor coat layer in the stated order from the side of the substrate; applying a side-chain type liquid crystal polymer to the anchor coat layer for homeotropic orientation; and fixing the polymer while the homeotropically oriented state is maintained. The method involves the use of a polymer as a side-chain type liquid crystal polymer capable of forming a homeotropically oriented liquid crystal layer on a substrate provided with no vertical alignment layer.